INTANGIBLE ASSETS - Summary of Acquired Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Intangible Asset, Acquired, Finite-Lived [Line Items]
Gross Carrying Amount	$ 7,151,647	$ 7,150,959
Accumulated Amortization	(6,336,543)	(6,190,154)
Net Carrying Amount	815,104	960,805
Customer relationships
Intangible Asset, Acquired, Finite-Lived [Line Items]
Gross Carrying Amount	6,089,105	6,089,050
Accumulated Amortization	(5,282,174)	(5,137,180)
Net Carrying Amount	$ 806,931	951,870
Customer relationships | Minimum
Intangible Asset, Acquired, Finite-Lived [Line Items]
Estimated Useful Lives	1 year
Customer relationships | Maximum
Intangible Asset, Acquired, Finite-Lived [Line Items]
Estimated Useful Lives	18 years
Trade names
Intangible Asset, Acquired, Finite-Lived [Line Items]
Gross Carrying Amount	$ 1,010,000	1,010,000
Accumulated Amortization	(1,010,000)	(1,010,000)
Net Carrying Amount	$ 0	0
Trade names | Minimum
Intangible Asset, Acquired, Finite-Lived [Line Items]
Estimated Useful Lives	4 years
Trade names | Maximum
Intangible Asset, Acquired, Finite-Lived [Line Items]
Estimated Useful Lives	7 years
Other amortizable intangibles
Intangible Asset, Acquired, Finite-Lived [Line Items]
Gross Carrying Amount	$ 52,542	51,909
Accumulated Amortization	(44,369)	(42,974)
Net Carrying Amount	$ 8,173	$ 8,935
Other amortizable intangibles | Minimum
Intangible Asset, Acquired, Finite-Lived [Line Items]
Estimated Useful Lives	1 year
Other amortizable intangibles | Maximum
Intangible Asset, Acquired, Finite-Lived [Line Items]
Estimated Useful Lives	15 years